JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/lang/AssertionStatusDirectives.java

/*
 * Copyright (c) 2000, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.lang;

/**
 * A collection of assertion status directives (such as "enable assertions
 * in package p" or "disable assertions in class c").  This class is used by
 * the JVM to communicate the assertion status directives implied by
 * the <tt>java</tt> command line flags <tt>-enableassertions</tt>
 * (<tt>-ea</tt>) and <tt>-disableassertions</tt> (<tt>-da</tt>).
 *
 * @since  1.4
 * @author Josh Bloch
 */
class AssertionStatusDirectives {
    /**
     * The classes for which assertions are to be enabled or disabled.
     * The strings in this array are fully qualified class names (for
     * example,"com.xyz.foo.Bar").
     */
    String[] classes;

    /**
     * A parallel array to <tt>classes</tt>, indicating whether each class
     * is to have assertions enabled or disabled.  A value of <tt>true</tt>
     * for <tt>classEnabled[i]</tt> indicates that the class named by
     * <tt>classes[i]</tt> should have assertions enabled; a value of
     * <tt>false</tt> indicates that it should have classes disabled.
     * This array must have the same number of elements as <tt>classes</tt>.
     *
     * <p>In the case of conflicting directives for the same class, the
     * last directive for a given class wins.  In other words, if a string
     * <tt>s</tt> appears multiple times in the <tt>classes</tt> array
     * and <tt>i</tt> is the highest integer for which
     * <tt>classes[i].equals(s)</tt>, then <tt>classEnabled[i]</tt>
     * indicates whether assertions are to be enabled in class <tt>s</tt>.
     */
    boolean[] classEnabled;

    /**
     * The package-trees for which assertions are to be enabled or disabled.
     * The strings in this array are compete or partial package names
     * (for example, "com.xyz" or "com.xyz.foo").
     */
    String[] packages;

    /**
     * A parallel array to <tt>packages</tt>, indicating whether each
     * package-tree is to have assertions enabled or disabled.  A value of
     * <tt>true</tt> for <tt>packageEnabled[i]</tt> indicates that the
     * package-tree named by <tt>packages[i]</tt> should have assertions
     * enabled; a value of <tt>false</tt> indicates that it should have
     * assertions disabled.  This array must have the same number of
     * elements as <tt>packages</tt>.
     *
     * In the case of conflicting directives for the same package-tree, the
     * last directive for a given package-tree wins.  In other words, if a
     * string <tt>s</tt> appears multiple times in the <tt>packages</tt> array
     * and <tt>i</tt> is the highest integer for which
     * <tt>packages[i].equals(s)</tt>, then <tt>packageEnabled[i]</tt>
     * indicates whether assertions are to be enabled in package-tree
     * <tt>s</tt>.
     */
    boolean[] packageEnabled;

    /**
     * Whether or not assertions in non-system classes are to be enabled
     * by default.
     */
    boolean deflt;
}

⏎ java/lang/AssertionStatusDirectives.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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